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51.
Maria Vittoria Barbarulo Francesca Buiarelli Massino Ciardi Alberto Giarrusso Felice Rosati G. P. Cartoni 《Journal of separation science》1995,18(11):705-708
The metabolism of oxabolone cipionate, 17-(3-cyclopentyl-1-oxopropoxy)-4-hydroxyestr-4-en-3-one, a synthetic anabolic steroid, was investigated in man, the cumulative urinary excretion and the metabolism of the compounds being studied by GC-MS in both electron impact and chemical ionization modes. After administration by injection to volunteers, five different metabolities were detected in urine. The metabolites and the parent compound were detected in urine up to a week after administration. 相似文献
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Solvent-induced crystallization of quenched isotactic polypropylene (iPP) films in dichloromethane, cyclohexane, carbon tetrachloride, and chloroform has been investigated.WAXD, density, and DSC measurements indicate that smectic iPP films undergo a complex rearrangement of the structure in these liquids, leading to a process of crystallization.Transport properties of the dried samples, after the solvent treatment, show that the first stage of crystallization involves, in addition to the smectic phase, a fraction of amorphous phase, while further crystallization regards only the smectic phase.The morphology of the crystallized samples has been investigated by transmission electron microscopy following permanganic etching. No change in the basic morphology is found, although local organization showing splaying and branching appears clearer in the solvent crystallized samples than in the starting smectic sample. 相似文献
55.
Symmetric and non-symmetric 2,6-disubstituted morpholines were synthesized through regioselective nucleophilic ring opening of oxiranes with tosylamide under solid-liquid phase transfer catalysis (SL-PTC) conditions followed by cyclization of the tosylamido diols thus obtained and final deprotection of the corresponding N-tosyl morpholines. The morpholines prepared are interesting building blocks in the synthesis of pharmaceuticals and agrochemicals. 相似文献
56.
Liberata Guadagno Carlo Naddeo Concetta D'Aniello Luciano Di Maio Vittoria Vittoria Domenico Acierno 《Macromolecular Symposia》2002,180(1):23-32
Syndiotactic polypropylene (sPP) was cast-extruded with a laboratory single screw extruder, obtaining a crystalline and still highly transparent film. The structural studies showed that the film crystallized at room temperature in the disordered helical form I, containing a fraction of a mesophase with the chains in trans-planar conformation. X-ray patterns, taken either along the extrusion direction (MD) or along the orthogonal directions (TD and ND), indicated a low orientation of the c axis parallel to the machine direction (MD) and a partial orientation of the a axis along the transverse direction (TD). Mechanical properties performed in either direction showed a very similar behaviour, but a different strain at the breaking point. The mechanical parameters were derived in both directions. 相似文献
57.
Concetta D'Aniello Liberato Guadagno Carlo Naddeo Vittoria Vittoria 《Macromolecular rapid communications》2001,22(2):104-108
A syndiotactic poly(propylene) film (sPP), quenched from the melt at 0°C, was drawn at room temperature up to a draw ratio of λ = 6. The fibre was analysed under tension by X‐ray analysis and FTIR spectroscopy, showing the presence of the oriented crystalline form III described by Chatani, with the chains in trans‐planar conformation. Then it was unhooked, undergoing a large shrinkage, and reaching a length corresponding to a draw ratio of λ = 3.8. X‐ray and FTIR analysis showed that in the relaxed fibre, a conformational transition from the trans‐planar to the helical form occurred. The relaxed fibre was again submitted to increasing extensions up to λ = 6, step by step, and the elastic behaviour was analysed through the Mullins' curve and hysteresis cycles. It showed good elastic properties, which appear to be closely correlated to the conformational transition between helical and trans‐planar forms. 相似文献
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Siegfried Berninghaus Werner Güth M. Vittoria Levati Jianying Qiu 《International Journal of Game Theory》2011,40(1):179-198
In a duopoly market, aspiration levels express how much sellers want to earn given their expectations about the other’s behavior. We augment the sellers’ decision task by eliciting their profit aspiration. In a first experimental phase, whenever satisficing is not possible, sales choices, point beliefs, or aspiration levels have to be adapted. This allows us to compare “aspiration-based satisficing” to “aspiration adaptation”. In a second phase, testing the absorption of satisficing, participants are free to select non-satisficing sales profiles. The results reveal that most participants are satisficers who, in line with aspiration adaptation theory, tend to adjust aspiration levels and to keep sales behavior nearly unchanged. 相似文献
60.
Giovanna Palazzino Lucia Cecchi Vittoria Colotta Fabrizio Melani Guido Filacchioni 《Journal of heterocyclic chemistry》1989,26(1):71-75
The synthesis of 1,2,3,4-tetrahydropyrazolo[4,3-c][1]benzazepin-1-ones 1 and that of its 10-methyl derivative 2 is reported. The preparation of the latter from 3-(2-aminobenzyl)3-pyrazolin-5-one and triethyl ortho-formate gave as the main product a derivative of the new tricyclic ring system, pyrazolo[1,5-c][1,3]benzo-diazepine. The structures of the new compounds synthesized were assigned by means of a 13C nmr study. 相似文献